Radiospeaker



7, v H. P. DE GRAFF 4 RADIO SPEAKER Filed Nov. 16. 1926 2 SheetS-Sheet 1 INVENTOR BY Wbflgm i AT ORNEY DeC. 27, 1927.

H. P. DE GRAFF RADIO SPEAKER Filed Nov. 16. 1926 2 Sheets-Sheet 2 flZr moL lNVENTO a/gi/ym i ATT RNEY Patented Dec. 2?, 1927.

UhllTE STA'liaS HOWARD P. DE GBAFF, OF NEW YORK, N. Y.

RADIOSPEAKER.

Application filecl N ovemher 16, 1926. Serial No. 148,722.

My invention relates to radio speakers and it is my ob ect to produce an ornamental speaker which will have great volume of sound, clarity in reproduct'on, be dist nctive in appearance, and which can be cheaply produced.

In the drawing l. a trout view of my speaker; Fig. 2 a back view thereot: Fig. 3 a top view, partly in section of the speaker base; and Fig. at a cross-sectional View of the base.

Externally, the speaker presents the appearance of a piece of statuary l on a base 2, the base "forming; the reproducing device while the statuary is purely ornamental.

The base comprises a bottom plate 3, vertical side Walls l and a top 5, which top has a large central opening 6 and is provided with raised bosses 7. The top edges of the side walls 4 are carried above the top 5 and large sound outlets 8 are formed in the side Walls 4. A resonant dome piece 9, provided with lugs 9 is placed on the bosses 7 and tie bolts 10 pass through the dome piece lugs, the bosses 7 and the bottom plate 3 thereby locking all the parts together.

The speaker unit 11 is mounted on the bottom plate 3 with the end of the nipple 12 close to, but not in contact with, the inner face of the dome piece 9. The adjusting means 12 for the unit projects through the base plate 3. The figure 1, of any desired design, is mounted on the dome piece 9.

I prefer to make the entire base of res0 nant material as I find this gives better acoustic results than it dead material is used.

This construction results in a speaker in which the sound waves from the diaphragm of the unit are first thrown against the in soe of the dome piece causing it to resonate 0 and reflect the soundwaves downward. The annular, open space between the edge of the dome piece 9 and the top 5 of the base relieves air compression and prevents dampening" and m-ul'iled tones. The main volume 0t reflected, reinforced sound is sent out through the openings in the side Walls of the base.

This construction gives excellent acoustic results and is cheap to make and assemble while the finished speaker presents a distinctive and artistic appearance.

I claim a- 1. A radio speaker comprising'a bottom plate, a speaker unit mounted thereon, a nippile on said unit, apertured side walls, a top provided with a central opening and a resonant dome over said top aperture adjacent the speaker unit nipple and spaced at its edges from the top.

2. A radio speaker comprising a bottom plate, a speaker unitmounted thereon, a nipple on said unit, apertured side walls, a top provided with a central opening, bosses on said top, a dome piece over said opening, 65 lugs on said dome piece and tie bolts passing through the dome lugs, bosses and bottom plate to secure the parts together with an annular space between the dome and top.

In testimony whereof I have aiiiXed my signature.

HOWARD P. DE GRAFF. 

